Recirculating ball screws are basically leadscrews with
a train of ball bearings riding between the screw and nut in a recirculating
track. A large number of complex mating parts make assembly tolerances critical.

The screw profile has a rounded shape to conform to the recirculating balls.
The primary advantage of ball screws over leadscrews is higher efficiency,
or the amount of energy output for energy input in addition to predictable
service life and low wear rate.

Given the demanding tolerances and highly featured design, traditional machining
costs are high. The ball circulator is an ideal MIM part, small and complex.
By replacing a machined ball circulator with a metal injection molded part,
total costs are reduced with no sacrifice in performance.